Jump to content
SAU Community

Recommended Posts

Couldn't find any information on this when searching...

I have heard that on an RB25DET, the rubber flexible pipe from the AFM to the turbo often sucks closed at high boost? What are its limits in either power or boost levels, before it needs to be upgraded?

cheers,

Chris.

Link to comment
https://www.sau.com.au/forums/topic/114323-standard-afm-turbo-intake-pipe/
Share on other sites

On the R34GTT we started to run into problems around 245 rwkw. Boost was irrelevant, it's all about the airflow through the tube. How much resistance to airflow (boost) there is after the turbo has no effect whatsoever.

:( Cheersw :(

Would someone be able to tell me what the consequences of the rubber induction hose "sucking" closed e.g. boost drop/power drop?

Also i have been told that there should a metal winding through the induction hose too, my RB20 dosent have one so it is VERY easy to squeeze and collapse the pipe. Would it be worthwhile finding a RB20 one that has that bit in there, or just going a full metal induction pipe?

I don't believe they have any metal ribbing in them.. not the early rb20 ones anyhow.

You could always make some ribbing by winding some heavy wire around a cylinder of the same diameter as the tube. Then insert. Cheap non-bling option..

You could always make some ribbing by winding some heavy wire around a cylinder of the same diameter as the tube. Then insert. Cheap non-bling option..

haha yea thats true, i also woudnt get the uber cool extra loud turbo flutter without a metal induction pipe.

I think i will try finding some wire to put in there as a fix. I have also heard about people making up some bent steel piping and putting it inside the std rubber pipe.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Old Son, did you re-use the Holden ABS in the new shell or try a different module?
    • Yeah, nah. I had the actuator rod off it today. The arm will not move at all. Neither out, nor in. Yeah, you'd think so, but I've been thinking about that. Even when the actuator rod fell all the way off at the beginning of this saga, it would build more boost and faster in lower gears than it would in higher gears, and you'd think that that was the opposite of what should happen. But I strongly suspect that there is a thing with the gearing getting the revs to rise faster, that there must be some transient effect with the gas flow rate rising quickly, that you don't get with the more steady state case of the higher gears. Keep in mind - the gate is not shut in either of my weirdnesses. So things are not "normal". We normally think about a turbo spooling up (below the wastegate target) with the gate shut. I have all sorts of mental models running now where the gate is a little bit open, and having it stuck open allowing gas out while it should be going through the turbine has all sorts of weird effects (in these mental models). I'm thinking in the higher gears, the ex mani pressure builds to the point where enough gases spill out the wastegate to just prevent the pressure rising much more at all, or just creeping up, all the whole the revs are increasing and getting closer to the point where a gear shift becomes necessary.
    • Is it possibly wastegate actuator itself is sticking, or even the rod to flapper? Otherwise I reckon things are getting a bit rusty/worn   Also odd it won't boost in 3rd to 5th, but will in 1st, I'd expect the other way around with it slightly open as there's more time on your way to redline for it to spin up
    • Does anyone know ow what these two plugs are for and if they should be unplugged? Just put the dash back together and can't remember if these were plugged in before or unplugged! (Blue and white plugs) 🤦🏽‍♂️
    • Did some FASTing ...got the impression that the actual part# was a moot point ; seems all of these hardlines for coolant are discontinued/NLA... like, I take it you're after the hardline that bolts onto to the manifold...that's NLA according to amayama & nengun .... ...just to clear up some confusion, they typically mounted the AAC valve to the intake manifold somewhere near a coolant passage, so the body of the valve heats up & holds it open when engine's up to temp - no coolant flows through the valve, it's a mechanical, thermal connection.
×
×
  • Create New...